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diff --git a/metis/ccnx/forwarder/metis/tlv/metis_TlvExtent.h b/metis/ccnx/forwarder/metis/tlv/metis_TlvExtent.h
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+++ b/metis/ccnx/forwarder/metis/tlv/metis_TlvExtent.h
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2017 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * @file metis_TlvExtent.h
+ * @brief Defines the extent structure used to map a TLV packet
+ *
+ * In MetisTlvSkeleton, all the pertinent fields used by Metis are stored by their extent range in the
+ * received packet buffer.  An extent is (offset, length).
+ *
+ */
+#ifndef Metis_metis_tlv_Extent_h
+#define Metis_metis_tlv_Extent_h
+
+#include <stdint.h>
+#include <stdbool.h>
+
+/**
+ * Stores the location of a field within a buffer.
+ * The values are usually in host byte order.
+ */
+typedef struct metis_tlv_extent {
+    uint16_t offset;
+    uint16_t length;
+} MetisTlvExtent;
+
+/**
+ * Used to detect a "not found" or "not present" condition.
+ * Equal to { 0x0, 0x0 }, which is an invalid extent value.
+ */
+extern const MetisTlvExtent metisTlvExtent_NotFound;
+
+
+/**
+ * Determine if two MetisTlvExtent instances are equal.
+ *
+ * The following equivalence relations on non-null `MetisTlvExtent` instances are maintained:
+ *
+ *  * It is reflexive: for any non-null reference value x, `MetisTlvExtent_Equals(x, x)`
+ *      must return true.
+ *
+ *  * It is symmetric: for any non-null reference values x and y,
+ *    `metisTlvExtent_Equals(x, y)` must return true if and only if
+ *        `metisTlvExtent_Equals(y, x)` returns true.
+ *
+ *  * It is transitive: for any non-null reference values x, y, and z, if
+ *        `metisTlvExtent_Equals(x, y)` returns true and
+ *        `metisTlvExtent_Equals(y, z)` returns true,
+ *        then  `metisTlvExtent_Equals(x, z)` must return true.
+ *
+ *  * It is consistent: for any non-null reference values x and y, multiple
+ *      invocations of `metisTlvExtent_Equals(x, y)` consistently return true or
+ *      consistently return false.
+ *
+ *  * For any non-null reference value x, `metisTlvExtent_Equals(x, NULL)` must
+ *      return false.
+ *
+ * @param a A pointer to a `MetisTlvExtent` instance.
+ * @param b A pointer to a `MetisTlvExtent` instance.
+ * @return true if the two `MetisTlvExtent` instances are equal.
+ *
+ * Example:
+ * @code
+ * {
+ *    MetisTlvExtent *a = { .offset = 5, .length = 7 };
+ *    MetisTlvExtent *b = { .offset = 5, .length = 8 };
+ *
+ *    if (metisTlvExtent_Equals(a, b)) {
+ *        // true
+ *    } else {
+ *        // false (this is the block executed)
+ *    }
+ * }
+ * @endcode
+ */
+bool metisTlvExtent_Equals(const MetisTlvExtent *a, const MetisTlvExtent *b);
+#endif // Metis_metis_tlv_Extent_h